统计过程控制简介课件

1、连接控制图方法与流程改进方法 Link Control Chart methods to the Process Improvement Methodology TM 讨论不同类型的变差 Discuss different types of variation 介绍各种类型的控制图 Introduce various types of Control Charts 讨论如何解释控制图 Discuss the interpretation of Control Charts,目的Objectives,统计过程控制简介,统计过程控制简介,我们是否应该采取行动？ Should we take act

2、ion?,每天我们都被数据淹没,而且不得不作出决定 Every day we are flooded by data and we are forced to make decisions,工厂产量下降 Plants Output Decreases By 4% 美国贸易赤字增加亿 US Trade Deficit Rises By $40Billion 某公司获利比上季度降低亿 Company Xs Earnings Are Off $240Million From Previous Quarter,我们需要解释数据的方法 We Need Ways to Interpret Data,统计过

3、程控制简介,今天采集什么样的数据？ What Type Of Data Is Collected Today?,制造业 Manufacturing :_ 非制造业 Non-Manufacturing _,如何分析数据？ How Is It Analyzed?,制造业 Manufacturing :_ 非制造业 Non-Manufacturing _,得知数据好坏后该当如何？ What Happens If It Is Bad / Good?,制造业 Manufacturing :_ 非制造业 Non-Manufacturing _ _,统计过程控制简介,客户需求下限 Lower “Custom

4、er” Requirement,这一方法 THIS METHOD 告诉你关于客户的需求 Tells you where you are in regards to customers needs 不告诉你怎么满足用户需求及下一步怎么办 It will NOT tell you how you got there or what to do next,客户需求上限 Upper “Customer” Requirement,我们管理数据的方式过去(历史来讲)的方式 The Way We Manage Data Historically,不用管它,不会坏的 Leave It Alone.It Ain

5、t Broke,痛苦,受累 Pain - Donald J. Wheeler 博士 “Failure to use control charts to analyze data is one of the best ways known to mankind to: increase costs waste effort and lower morale.” - Dr. Donald J. Wheeler,统计流程控制图显示不同的解释,可为什么呢?SPC Tells A Different Story, But Why?,统计过程控制简介,S = 统计技术: 检查偏差 Statistical

6、techniques used to examine process variation,C = 控制过程通过积极管理 Controlling the process through active management,P = 过程, 任何过程 Process, ANY Process,现在我们管理数据的方法 - SPCThe Way We Manage Data - Today SPC,显示过程偏差随时间变化的图形,统计过程控制简介,控制图方法Control Charts Method它从哪里来的?Where Did It Come From?,19世纪20 年代- 西部电器 的 Walte

7、r Shewhart博士: 1920s - Western Electric / Dr. Walter Shewhart 惯于确认受控的 they are internal to the process 控制极限是根据样本数据计算得出的; 是过程的内部特征 Specification limits are determined by your performance standard; they are external to the process 规范极限是由执行的标准决定的; 是过程的外部特征 Know when a process is out of control: Western

8、Electric Rules. 知道过程何时失控: Western Electric规则 Control charts are only as good as the actions that you take to keep the process under control. 控制图和采取的纠正行动共同使过程保持受控,连续数据控制图小结Take AwaysVariable Control Charts,统计过程控制简介,Attribute Control Charts逻辑数据控制图,统计过程控制简介,属性型变量,连续型变量,数据类型？ 连续变量 VS 属性变量,数据分组还是单个数据 ?,缺

9、陷数 VS 缺陷比例 ?,GROUPS (Averages) (n1),INDIVIDUAL VALUES (n=1),X-Bar R X-Bar S,Individuals Moving Range,缺陷数,缺陷比例,Is The Probability Of A Defect Low ?,If You Know How Many Are Bad, Do You Know How Many Are Good?,Poisson Distribution,Binomial Distribution,Individuals Moving Range,NO,YES,YES,样本大小一定？,YES,N

10、O,c Chart,u Chart,样本大小一定？,np Chart,NO,YES,p Chart,如何选择控制图 Choosing the Correct Control Chart,NOTE: X-Bar S is appropriate for subgroup sizes (n) of 10,统计过程控制简介,重要定义 Important Definitions,A Defect (缺陷) A single characteristic that does not meet requirements 不满足要求的单一特性 A Defective (缺陷率) A unit that co

11、ntains one or more DEFECTS 包含单个或多个缺陷的单位,Attribute Charts Can Consider Either Case Depending On The Chart Type Chosen 根据所选择的控制图类型，逻辑数据控制图可以考虑两者之一的情形,统计过程控制简介,逻辑数据控制图的分类Classification of Attribute Chart Types,c,u,n p,p,Constant Lot / Unit Size 样本数不变,Variable Lot / Unit Size 样本数变化,Defects 缺陷数,Poisson 泊

12、松分布,Binomial 两项式分布,Defective 缺陷率,统计过程控制简介,Attribute Control Chart逻辑数据控制图C-Chart (C图),统计过程控制简介,属性型变量,连续型变量,数据类型？ 连续变量 VS 属性变量,数据分组还是单个数据 ?,缺陷数 VS 缺陷比例 ?,GROUPS (Averages) (n1),INDIVIDUAL VALUES (n=1),X-Bar R X-Bar S,Individuals Moving Range,缺陷数,缺陷比例,Is The Probability Of A Defect Low ?,If You Know Ho

13、w Many Are Bad, Do You Know How Many Are Good?,Poisson Distribution,Binomial Distribution,Individuals Moving Range,NO,YES,YES,样本大小一定？,YES,NO,c Chart,u Chart,样本大小一定？,np Chart,NO,YES,p Chart,如何选择控制图 Choosing the Correct Control Chart,NOTE: X-Bar S is appropriate for subgroup sizes (n) of 10,统计过程控制简介,C

14、-Chart (C图),Chart for defects per unit (subgroup) 描述每单位或子群所包含的缺陷的控制图 Based on Poisson distribution 根据泊松分布而来 High probability of finding defect of some type. Large samples are needed if defect probabilities are low. 发现某些缺陷的可能性高；如果缺陷概率低的话，需要大样本。 Lower probability of a defect of a given type 特定类型缺陷发生的可

15、能性低 Works best on complex unit of product 在产品单元复杂时效果最佳 Constant subgroup/lot size 子样大小为常数,统计过程控制简介,C图实例,Attribute Data逻辑数据 Manufacturing data indicates that a significant loss occurs from welding nonconformances on part A detected at NDT. The data on the number and general type of nonconformity for

16、each part tested is maintained by serial number in the NDT log books. 生产数据表明部件A的焊接不合格造成了可观的损失，测试的每个部件不合格的数目和类型都有相应的记录。 To determine the current performance of the welding process we will plot the number of nonconformities per subgroup of two parts on a C-Chart using the data from the log book: 为了确定目

17、前焊接过程的表现，根据记录的数据用C图画出每一子样(2个部件)的不合格数,Date日期 6/16/26/36/46/56/86/9,Number of 4 2 5 6 10 5 6 Nonconf. 3 2 8 5 76 per 7 4 9 9 Subgroup 每一子样的 不合格数 7 5 7 4 5 6 6 7,Example Part I.实例第一部分： The , column weld_I, contains the data given above. 以上数据在文件C_chart中的weld_I列 1.Using Minitab, create a C-Chart. 用Minita

18、b画出C图 2.Is the high level of nonconformance we are experiencing due to an assignable cause or random variation? 目前的高水平的不合格品是由可归因原因还是随机原因引起的偏差 3.What are some actions for consideration to reduce the level of nonconformances generated by this process? 为了降低过程的不合格水平，需要考虑采取什么措施？ 4. What is the Process Ca

19、pability? 过程能力怎样,统计过程控制简介,MINITAB FILE: C chart.mtw MINITAB文件: C chart.mtw,C图实例,统计过程控制简介,C图实例,统计过程控制简介,Attribute Control Charts逻辑数据控制图U-Chart (U图),统计过程控制简介,属性型变量,连续型变量,数据类型？ 连续变量 VS 属性变量,数据分组还是单个数据 ?,缺陷数 VS 缺陷比例 ?,GROUPS (Averages) (n1),INDIVIDUAL VALUES (n=1),X-Bar R X-Bar S,Individuals Moving Rang

20、e,缺陷数,缺陷比例,Is The Probability Of A Defect Low ?,If You Know How Many Are Bad, Do You Know How Many Are Good?,Poisson Distribution,Binomial Distribution,Individuals Moving Range,NO,YES,YES,样本大小一定？,YES,NO,c Chart,u Chart,样本大小一定？,np Chart,NO,YES,p Chart,如何选择控制图 Choosing the Correct Control Chart,NOTE:

21、X-Bar S is appropriate for subgroup sizes (n) of 10,统计过程控制简介,U-Chart - defects per unit, variable lot (subgroup) size U图描述子样数变化时每单元的缺陷数 Same logic as C-Chart, except variable lot (subgroup) size (n) 除了子样数n可变外，原理与C图相同,U图,统计过程控制简介,In , column “errors” contains time order data of customer parts order d

22、efects found each day. A defect is defined to be inaccurate information found on a parts order requisition. Both the number of defects and the daily number of orders are recorded. 在文件U_chart.mtw的“errors”列中记录了每天发现的客户零件订单缺陷的数据. 缺陷定义为在零件订货单上发现的不准确信息，缺陷数和每天的订单数都有记录。 Using Minitab, construct a U-Chart of

23、 the data. 用数据在Minitab中画出U图 Using the Six Sigma Product Report obtain the Process Capability data for this parts ordering operation. 用Six Sigma Product Report 得出零件订货操作过程的过程能力数据 What are your observations?观察结果如何？,U图实例,统计过程控制简介,MINITAB FILE: U_Chart.mtw MINITAB文件: U_Chart.mtw,U图实例,统计过程控制简介,U图实例,统计过程控制

24、简介,Attribute Control Charts逻辑数据控制图P-Chart (P图),统计过程控制简介,属性型变量,连续型变量,数据类型？ 连续变量 VS 属性变量,数据分组还是单个数据 ?,缺陷数 VS 缺陷比例 ?,GROUPS (Averages) (n1),INDIVIDUAL VALUES (n=1),X-Bar R X-Bar S,Individuals Moving Range,缺陷数,缺陷比例,Is The Probability Of A Defect Low ?,If You Know How Many Are Bad, Do You Know How Many A

25、re Good?,Poisson Distribution,Binomial Distribution,Individuals Moving Range,NO,YES,YES,样本大小一定？,YES,NO,c Chart,u Chart,样本大小一定？,np Chart,NO,YES,p Chart,如何选择控制图 Choosing the Correct Control Chart,NOTE: X-Bar S is appropriate for subgroup sizes (n) of 10,统计过程控制简介,MINITAB FILE: P chart.mtw (MINITAB文件: P

26、 chart.mtw),In , column “voids” contains data for number of parts containing coating voids found at inspection after a coating operation. 在文件P_chart.mtw中的“voids”列记录了在涂层操作后的检测中发现的包含无效涂层的零件数。 Using Minitab, create a P-Chart of the data. 根据数据在Minitab中画出P图 What are your observations? What is needed to e

27、stimate the Process Capability? 观察结论是什么？为估计过程能力，还需要什么信息？,P图实例,统计过程控制简介,P图实例,统计过程控制简介,Attribute Control Charts逻辑数据控制图NP-Chart (NP图),统计过程控制简介,属性型变量,连续型变量,数据类型？ 连续变量 VS 属性变量,数据分组还是单个数据 ?,缺陷数 VS 缺陷比例 ?,GROUPS (Averages) (n1),INDIVIDUAL VALUES (n=1),X-Bar R X-Bar S,Individuals Moving Range,缺陷数,缺陷比例,Is Th

28、e Probability Of A Defect Low ?,If You Know How Many Are Bad, Do You Know How Many Are Good?,Poisson Distribution,Binomial Distribution,Individuals Moving Range,NO,YES,YES,样本大小一定？,YES,NO,c Chart,u Chart,样本大小一定？,np Chart,NO,YES,p Chart,如何选择控制图 Choosing the Correct Control Chart,NOTE: X-Bar S is appro

29、priate for subgroup sizes (n) of 10,统计过程控制简介,NP-chart: number conforming in subgroup NP图：子样大小一致 Same logic as the p-chart, except constant lot size (n) 除子样大小n恒定外，原理同P图,NP图,统计过程控制简介,In , column “switches” contains inspection data from 25 consecutive lots of electrical switches. 在文件Np_chart.mtw中的“swit

30、ches”列中记录了25组连续 的电器开关子样的测试数据 。 The lot size is constant at 100 switches per lot. 子样大小为每组恒定100个电器开关。 Using Minitab, create an Np-Chart of the data. 根据数据在Minitab中画出NP图。 What are your observations? 观察结论是什么？ What is the Process Capability? What do you need to know to answer this? 过程能力怎样？为了回答这一问题，需要做些什么？

31、,NP图,统计过程控制简介,MINITAB FILE: Np chart.mtw MINITAB文件: Np chart.mtw,NP图,统计过程控制简介,NP图,统计过程控制简介,逻辑数据控制图小结 Summary of Attribute Charts,Useful when variable data not available 当连续数据无法得到是很有用 Use count/classification datapass/fail, good/bad 使用诸如合格/不合格、好/坏等记数/分类数据 Same general rules for interpretation as vari

32、able charts 一些通用规则与连续数据控制图相同 Useful as end-to-end overview; use variable charts for further study of problems 对分析概况很有用，使用连续数据控制图对问题可做进一步研究 Can use data gathered for other purposes 可使用为其它目的收集的数据 Generally less expensive to administer, but tell you less 通常需要较少资源管理，但得到的信息亦较少,统计过程控制简介,Shortcomings 缺点： I

33、ncluding too many variables makes interpretation difficult 包含太多变量，使解释较为困难 Must fit the parameters you are evaluating to theoretical distribution Poisson (C, U-Charts), Binomial (P, NP-Charts) 必须满足所评估的参数的理论分布(C图U图泊松分布、P图NP图二项式分布) Need to evaluate whether constant/non-constant lot size will help you w

34、ith root cause analysis 须评估子样大小是否恒定对根本原因分析的影响 Sensitivity is dependent on magnitude of defect level 敏感性取决于数量和缺陷水平,逻辑数据控制图小结 Summary of Attribute Charts,统计过程控制简介,Attribute control charts are used to monitor the level of nonconformance of a process. 逻辑数据控制图用来监控过程不合格品的水平 Select the appropriate attribut

35、e control chart based upon 根据以下两项选择适当的逻辑数据控制图 constant vs. variable lot size子样大小是否恒定 defects vs. defectives缺陷数/缺陷率 Defect (缺陷) A single characteristic that does not meet requirements 不满足要求的单一特性 Defective (缺陷率) A unit that contains one or more DEFECTS 包含单个或多个缺陷的单位,逻辑数据控制图小结 Summary of Attribute Chart

36、s,统计过程控制简介,对控制图有效使用的要求 Requirements for Effective Use of Control Charts,管理必须建立并且支持促进适当的行动，且支持对控制图 上信息的收集 Management MUST establish and support an environment that promotes proper action and support to the information collected on the control charts 控制图只在改善能够给公司或客户带来好处的过程中运用实施 Control Charts are impl

37、emented ONLY on Key Processes on which improvement will bring benefit to the organization and/or the customer 数据从能力测量系统中收集的过程是有效的 Data collected from the process is validated through the use of a CAPABLE measurement system,控制图程序的最大问题 Biggest Failure Of Control Chart Programs 系统被控制图淹没，没有对数据做任何行动 Floo

38、d the system with control charts,then dont take action on the data,统计过程控制简介,分组：案例学习1Sub-grouping: Case Study #1,Paccar 要求一个康明斯发动机厂运行X 条- R 图过程的特征: 油漆厚度 A Cummins engine plant was asked by Paccar to run X bar - R charts on a process characteristic: paint thickness 名字至少5 种不同方式X - R 图能被设定 Name at least

39、 5 different ways an X bar - R chart could be setup 1. _ 2. _ 3. _ 4. _ 5. _,统计过程控制简介,计划2: Plan 2: 每天将有5个发动机被取样 5 engines will be sampled each day 5个发动机从一个油漆点选取 The 5 engines are selected from one paint booth 5个发动机喷涂的平均厚度绘制当天的点 Paint thickness for the 5 engines are averaged together to plot that day

40、s point 第二天将选择另外油漆点的 On the following day another paint booth is selected,分组：案例学习2Subgrouping: Case Study #2,Paccar 告诉康明斯发动机厂开始运用X 条- R 图的过程特征:喷涂厚度。工程师们提出了2 个不同计划，并谈论各个方法的利弊。 Cummins Engine Plant was told by Paccar to begin running X bar - R charts on a process characteristic: paint thickness. The e

41、ngineering team proposed 2 different plans. Discuss pros and cons of each method.,计划1 Plan 1： 每天将有5个发动机被取样 5 engines will be sampled each day 从每5个油漆点选取1个发动机 1 engine is selected from each of the 5 paint booths 5个发动机喷涂的平均厚度绘制当天的点 Paint thickness for the 5 engines are averaged together to plot that da

42、ys point,统计过程控制简介,Mch 1 Mch 2 Mch 3 Mch 4 Mch 5Avg 20.34 20.64 19.94 24.42 24.0221.87 19.22 19.05 20.79 25.39 23.7821.64 18.53 22.23 19.92 25.04 23.4921.84 20.22 20.07 19.79 22.30 24.0221.28 21.15 19.72 21.53 23.10 25.1922.13 19.39 20.80 19.21 24.03 23.6221.41 .,Day 1,Day 2,Day 4,Day 5,Day 6,Day 3,案

43、例学习2：计划1个样本数据Case Study #2: Plan 1 Sample Data,统计过程控制简介,Sam 1 Sam 2 Sam 3 Sam 4 Sam 5Avg Day 1 Mch 1 19.41 19.11 21.26 20.61 20.0920.01 Day 2 Mch 2 20.20 20.78 20.76 19.41 19.5520.14 Day 3 Mch 3 18.75 19.01 20.18 17.81 20.0019.15 Day 4 Mch 4 24.59 24.11 24.53 26.00 23.7924.60 Day 5 Mch 5 22.59 23.71

44、 23.28 23.52 25.8623.79 Day 6 Mch 1 20.16 20.97 20.25 19.98 19.3620.14 Day 7 Mch 2 20.56 20.29 20.55 21.85 19.7420.60 .,案例学习2：计划2个样本数据Case Study # 2: Plan 2 Sample Data,统计过程控制简介,案例学习：计划1Case Study # 2: Plan 1,统计过程控制简介,案例学习Case Study # 2: Plan 2,统计过程控制简介,案例学习：计划2 附加信息Case Study #2: Plan 2 Additional

45、Information,数据确认所知工程事实: Data confirms known engineering facts: 点1,2, 和3的表现不同于点4 和5的 Booths 1,2, and 3 perform differently than booths 4 and 5,统计过程控制简介,BB Hints,现在。至少在一个控制图上跟踪你的Y轴! Track your Y(s) in at least one control chart, NOW ! 在自学时, 找到最合适你的项目的图表 With self study, learn the chart(s) that are mos

46、t appropriate to your project 准备开始跟踪你重要的X轴 Be prepared to start tracking your important X(s) 我们将在许多领域使用控制图 We will use control charts in many areas MSA, 能力研究, Multi-Vari 研究 MSA, Capability Studies, Multi-Vari Studies,统计过程控制简介,统计过程控制- 摘要SPC - Summary,连接的控制图与DMAIC 路线图方法 Linked Control Chart Methods to

47、 the DMAIC roadmap 讨论的不同类型的偏差 Discussed different types of variation 介绍的各种各样的控制图类型 Introduced various Control Chart types 讨论的控制图的解释 Discussed the interpretation of Control Charts,统计过程控制简介,目的: Objective: 分析专题研究如果你是销售副总裁，然后作为地方销售经理的 Analyze the Case Study as if you were the VP of Sales and then as one

48、 of the Regional Sales Managers 这是怎么回事? Whats Going On Here ?,质量进步- 1997 年6月Quality Progress - June 1997 “怎么教其他人运用统计思维 “How To Teach Others To Apply Statistical Thinking” By Roger Hoerl, Galen Britz, Don Emerling, Lynne Hare, Janice Shade,案例学习CASE STUDY,统计过程控制简介,假设Selit 公司, 销售的副总Ron Hagler, 得到一个报告关于

49、过去五年他管理之下的区域季度销售数据。他不满意其结果, 打电话对他的秘书说。“Marsha, 告诉地方经理我今天有话要说，今天下午大家必须出席!” Suppose that Ron Hagler, the vice president of sales for Selit Corp, had just gotten a report on the past five years of quarterly sales data for the regions under his authority. Not happy with the results, he got on the phone

50、to his secretary. “Marsha, tell the regional managers I need to speak with them this afternoon. Everyone must attend !” Marsha 是Hagler 的秘书干了快十年。她知道由他声音和口气意味着什么, 因此她与区域经理联系下午2 点召开紧急会议。在1:55 pm,区域经理都到了。当Hagler不高兴的时候他们被叫如会议室。 Marsha had been Haglers secretary for almost a decade. She knew by the tone i

51、n his voice that he meant business, so she contacted the regional managers about the impromptu meeting at 2 pm. At 1:55 pm, the regional managers filed into the room. The only time they were called into a meeting together was when Hagler was unhappy. Hagler 上来直接说“我刚收到季度销售报告。东北销售是意想不到的。史蒂夫, 您不仅在第四嫉妒增

52、长了17.6%, 并且全年比去年大幅增加了20.6% 。我不知道您怎么做的!”。史蒂夫微笑。他的关于在年末让客户大批储蓄的方式再次成功了。 Hagler wasted no time. “I just received the quarterly sales report. Northeast sales were fantastic. Steve, you not only improved 17.6% in the fourth quarter, but you also increased sales a whopping 20.6% over the previous year. I

53、dont know how you do it !”. Steve smiled. His philosophy to end the year with a bang by getting customers to stockpile units paid off again. Hagler 继续: “Terry, 西南销售也不错。您显示了第四季度增量11.7% 和11.8% 年度增长”。Terry也在微笑。她不肯定他那么很好, 但她肯定什么也不会改变。 Hagler continued: “Terry, Southwest sales were also super. You showed

54、 an 11.7% increase in the fourth quarter and an 11.8% increase over the previous year”. Terry also smiled. She wasnt sure how she did so well, but she sure wasnt going to change anything. “Jan,在第四季度西北销售上升了17.2%, 但比去年下降8.2% 。” Hagler 说。“你应该发现你应该早些做点什么什么以把你的销售有所突破。即使如此, 您的表现在第四季度是好的“Jan设法掩藏他的尴尬。虽然他在11

55、月收到一个大定单，, 这是他在很长时间内的收到的第一个大订单。 Jan, Northwest sales were up 17.2% in the fourth quarter, but down 8.2% from the previous year.” said Hagler. “You need to find out what you did previously to make your sales go through the roof. Even so, your performance in the fourth quarter was good” Jan tried to h

56、ide his puzzlement. Although he had received a big order in November, it was the first big order he had receive in a long time.,Quality Progress - June 1997 “How To Teach Others To Apply Statistical Thinking” By Roger Hoerl (GE), Galen Britz, Don Emerling, Lynne Hare, Janice Shade,统计过程控制简介,Hagler 现在

57、准备处理“问题” 地区。“Leslie, 北部中央销售第四季度下降5.5%, 但比去年高4.7%。我理解你的销售变化这么大。是否你需要更多的奖金?” Leslie 低下头。过去五年她工作非常艰苦并签了许多新客户。实际上, 1994 年她还获得新客户开发的奖金。 Hagler was now ready to deal with the “problem” regions. “Leslie, North Central sales were down 5.5% in the fourth quarter, but up 4.7% from the previous year. I dont un

58、derstand how your sales vary so much. Do you need more incentive?” Leslie looked down. She had been working very hard the past five years and had acquired numerous new accounts. In fact, she received a bonus for acquiring the most new business in 1994. “KIM, 中大西洋销售第四季度下降3.2%并比去年下降2.6%。我对您的表现非常失望。您曾经是我最佳的销售代表。我对你有很高的期望。现在, 我只能希望